What is the preferred site for tuberculosis skin test?

What is the preferred site for tuberculosis skin test?

• A. Upper Back
• B. Anterior Forearm
• C. Thorax
• D. Abdomen

Answer: (B)

The main idea is that the tuberculin skin test (Mantoux) must be placed intradermally on a site that allows a clean, easily readable reaction. The inner surface of the forearm (anterior forearm) is ideal because it provides a flat, accessible area with relatively uniform skin and minimal subcutaneous variation. This makes it straightforward to inject just into the dermis and to read the resulting induration (not just redness) 48–72 hours later. Other sites such as the upper back, thorax, or abdomen are harder to read accurately, may involve more tissue variation, or risk injection depth that alters the reaction, leading to unreliable results.

The main idea is that the tuberculin skin test (Mantoux) must be placed intradermally on a site that allows a clean, easily readable reaction. The inner surface of the forearm (anterior forearm) is ideal because it provides a flat, accessible area with relatively uniform skin and minimal subcutaneous variation. This makes it straightforward to inject just into the dermis and to read the resulting induration (not just redness) 48–72 hours later.

Other sites such as the upper back, thorax, or abdomen are harder to read accurately, may involve more tissue variation, or risk injection depth that alters the reaction, leading to unreliable results.